This has just been posted on a live news feed:

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margaret georgiadou
@madgie1941


Hi - am the person responsible for the Revoke Art 50 petition. Just needed to tell you that 1. am currently visiting Cyprus. and 2. last night I had three telepohoned death threats. (!) Who wants Brexit so much that they are prepared to kill for it?
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You may choose to say she started the threats if you like. But I doubt if she telephoned Number 10 specifically.